Recently, social games which can be readily played outside of the home by a game player using a terminal device such as a mobile phone, a smartphone, or a tablet device have become increasingly widespread. Unlike conventional games in which a game player's skill is an important factor, a social game is usually a game in which an ability score of a team or the like belonging to a game player can be increased solely by simple button manipulations and is a game that can be readily played by a game player. Therefore, social games are often played to pass the time when waiting for a train or when waiting for someone. In addition, while social games also enable teams owned by game players to match up against one another, the outcome of the match-up is also instantaneously determined based on a magnitude relationship between ability scores of the teams owned by the game players regardless of the skills of the game players. Furthermore, results such as an increase or decrease in the ability score of a team and an acquisition or loss of an item are released at the same time as the outcome. Such promptness and simplicity are features of social games.
Another feature of social games is their billing system. For example, a mode is widely adopted where a game player desiring to increase an ability score of a team owned by the game player in an efficient manner is billed as follows. Accordingly, a game operating company which operates a social game forum and a game maker which provides a game of their creation can make profits.
Specifically, a game player purchases an item for increasing the ability score of a team owned by the game player or an item (a drink or medication) for restoring hit points of a character that is a member of the team owned by the game player, and the like.
Items for hit point restoration will now be further described. Obviously, once hit points of a character are reduced to zero, a game player is no longer able to continue the game. However, as time passes without a further change in status, the hit points of the character are gradually regained and the game can be executed one again once the hit points are restored to a predetermined level. However, during this period, since the game player is unable to carry on with the game, the ability score of the team cannot be increased. Therefore, if the game player wishes to increase the abilities of a character as quickly as possible, the game player either executes the game as soon as the hit points are restored or frequently accesses the game in order to check whether the hit points have been restored or not. However, since such methods require a certain amount of time and trouble, the game player may feel a sense of inconvenience. As a result, such a game player purchases an item (a drink or medicine) that restores the hit points of a character or, in other words, the game player buys time with money. In particular, with a social game in which a game is simultaneously executed by a large number of game players, a game player often desires to improve his/her own ranking through enhancing abilities by even the slightest margin over other game players. Therefore, there are cases where a game player chooses to improve abilities quickly or ahead of other game players while being fully aware that he/she is to be billed instead of gradually enhancing abilities over time.
Patent Documents 1 and 2 are disclosed as prior art documents related to the present application. Patent Document 1 discloses a technique to present a game player with items that can be acquired by the game player depending on game status. Patent Document 2 discloses a technique that enables a game player to purchase an item without interrupting a game.
As described above, conventionally, methods of ability improvement in social games can be roughly divided into the following two options: 1. taking time (checking whether or not hit points have been restored in order to enhance abilities efficiently, and increasing frequency of access to the game in order to ensure game continuation); and 2. purchasing an item or the like. However, if there are only these two options, a significant gap is created in the degree of ability improvement between game players with sufficient financial resources who purchase one item or the like after another and game players who simply play the game by taking time. In addition, game players who simply take time tend to think that even if they purchase a certain amount of items, they would fall well short of those who buy items in large quantities after all. Therefore, these game players cannot be motivated to actively purchase items.
Consequently, the present state of social games is that a clear line is being drawn between billable game players and non-billable game players. However, should this state continue, since rankings of non-billable game players would hardly rise, if at all, there is a reasonable possibility that their sense of participation to the game may gradually decline and that they may stop playing the game. In other words, as things stand, a social game system has an intrinsic risk in its inability to provide sufficient motivation for non-billable game players to continue playing.
A conceivable solution to this problem is to provide previously non-billable game players with motivation to become billable players or, in other words, provide a variation in terms of ability improvement which had not been available in conventional games.
Patent Document 1: Japanese Patent Application Laid-open No. 2006-94877
Patent Document 2: Japanese Patent Application Laid-open No. 2010-282356